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inlineeight 10-01-2012 03:57 PM

straighteight upgrade
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I,m considering to upgrade my inlineeight in my 36 century coupe. I'm looking for just a little more horse power but not making a screamer. Possibly headers & intake change. Might use an electric fan & aluminum radiator and also electric fuel pump.. I,m mostly a purest in the old car hobby but I think I,m ready to step it up. Any suggestions? Does anyone make headers?

farna 10-01-2012 04:12 PM

Uh, no... nobody make anything! There's not much you can do. You can make your own headers, of course. Heck, I'd start with two right side V-8 headers and make a flange to fit the I-8. That might work... Or just get a "make your own" kit and start cutting and welding.

The intake would be harder. You can make a steel tubing intake similar to making a header though. Would be real easy to make intake tubes for Weber side drafts! Four 2V Webers sticking out the side would look great!!

Call Isky, Crane, or some other cam grinder and see if they can still grind a cam that long. They won't have new blanks, but can easily regrind a stock cam and get you a bit more power.

Cape Cod Bob 10-01-2012 07:25 PM

Have you ndriven this car. Seems that I remember some straight eights that had a lot of stock power.:welcome:

AutoGear 10-02-2012 09:10 AM

Harvey Crane still does some oddball/ specialty cam regrinding; might try him. I think he is in his 90s now.

Don't go too crazy without evaluating the oiling system on this thing; along with the con rods and the hardware that holds the con rods together.

Im not sure about the valvetrain, but if its not adjustable, you can't do too much to the cam either. Best thing you can do to increase performance is more compression and or rear gear change.

monster76 10-02-2012 10:09 AM

Dont ask me why but i have always wanted to build an old straight 8 fuel injected and stuff in an old henry j just one of my old odd ball ideas. Any way as far as headers i think you are going to end up having some made or building them your self the same goes for the intake 10-02-2012 04:03 PM

Back in the day, when I was drag racing. There was a Henry J with a Hudson six in it. Ran every week at my favorite track. I ran B/Gas and they would let that car go first. A LOOONG wait for my green!!

Irelands child 10-02-2012 04:43 PM

You kinda said what you want to do with this .... so picking at what's left of my brain, these old straight 8 Buicks had individually poured tin-lead babbit rod bearings which are then fitted to the crankshaft dimensions cylinder by cylinder at least through 1948. This will severely limit how much you can safely add horsepower to these low RPM engines. Then there are those main bearings - reamed to size and fitted to the crankshaft with shims. My thoughts are, fix it up as-is and drive it. 320 cubic inches in that Century wont move it fast, but will have a lot of low end torque. If you have a later version straight 8 that could be installed, i.e. '49-'53, then I think you have some more possibilities with an improved bottom end as well as oiling system. This one, probably looking at a recipe for failure with horsepower modifications. Of course, with a 'nailhead' V8 installed there ............:D:D

Dave W

455olds 10-02-2012 08:50 PM

They had factory available dual carb intakes for those engines. That and a home built header will help a lot.

timothale 10-02-2012 09:26 PM

carter wcd carbs
G m used carter WCD 2 barrels on those dual setups/. They were a pretty good carb and had metering rods that you could adjust the lifter cam on the linkage , The WCD's we used by american motors up thru the 70's, In the 60's you could still buy the weld on flange kits to add more carbs to your stock manifold. I made my own a few years ago and made a spider leg intake manifold for my corvair (6 cyl flat engine ) powered dunebuggy and ran a single holly 500 2 Barrel carb.

Highball 10-19-2012 12:49 AM

straighteight upgrade
4 Attachment(s)
The Buick OHV straight eights had a performance package called the "Century" engine. The early versions were 246 cubic inches, later 263 and finally a 320. All could be made to scoot. My family still has a '41 Sedanette Century and it runs very well. The engine in the roadster is a 320. The one in the Sedanette is a 263.

techinspector1 10-19-2012 01:24 AM

I think the simplest way would be to rig up a small supercharger or turbo. Seems that with 4-5 psi, you could make more power than you could with more carbs and headers and not blow up anything.

farna 10-19-2012 09:00 AM

Great call Tech!! Pressurizing the intake should deliver fuel more evenly too. A "draw through" setup would be easiest with low boost like that.

hcompton 10-19-2012 09:31 AM

Does edelbrock still make a webber and four barrel manifold for these. i bet they got one in stock somewhere. i would give em a call. I was thinking there were parts out there for s8 fords.

biggest problem you got is young guys dont do straight 8 stuff and old dudes dont like to sell stuff on the net. Best to hit the swap meets and ask every person that will talk to you if they have herd of anyone with the parts you need. they were made by a bunch of people at one time. I am sure some old rodder has what you need in his garage in good shape and ready to go.

I would not boost a 100 year of engine. or 80 90 whatever. Unless you have just rebuilt it i would leave that option on the table. Putting the stright 8 in storage and going 350 would be safer. You could always go back to oem spec.

Boost will have oil pooring out of that motor. Not to mention putting load on everything. If you do boost it you got to build it up to take the turbo. gaskets and valve seals were never made to take that kind of abuse they will be spewing oil. i was thinking the crankcase does not have good venting on those old 8s as well. But i have never built one. 350 is to cheap and no one cries when it goes up in smoke. junk yard short block and fab up some custom mounts so you dont have to cut into your chassis would be trick. i think they fit if you lower the front of the car and mount the engine back at an angle.

hope that is not unwanted advise.

farna 10-19-2012 10:12 AM

Ford NEVER made a straight-8 engine, only V-8s.

Boosting the old engine with moderate boost (5-6 psi) shouldn't be a problem at all. Pistons are much heavier and thicker if aluminum, and may be cast iron. The crank and rods are forged steel, cast wasn't strong enough until techniques were developed around 62-63. The cylinder walls are thicker due to casting techniques not developed until the early 60s for thinner blocks. Everything is tough enough, but you do make a good point of making sure everything is in good working condition or better yet newly rebuilt. Detonation would be a concern, but that would be the case on a modern engine. Cast iron pistons might not be tougher than cast aluminum -- heavier an thicker, but also more brittle.

hcompton 10-19-2012 10:31 AM

Shows what i know next to nothing about stuff that old. i am like a kid with his dads stereo when it comes to turbos. If theres a HP knob i am going to turn it all the way up. So I would have to pass on the turbo. I know my self to well.

edelbrock does flat head ford stuff still not sure if they do anything else. They never list everything they sell on the site.

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